As of 2015, the Center for Science in the Public Interest cautions against the use of sucralose, marketed as Splenda, after an unpublished study indicated a higher risk for leukemia, according to Medical News Today. The study was conducted on more than 800 lab mice over their lifespans.
Larger studies still need to be conducted on humans to determine if there is a similar risk for cancer, so pregnant women and children avoid consuming artificial sweeteners until they are proven safe, cautions Medical News Today. Artificial sweeteners such as sucralose, aspartame and saccharine are used in a variety of food products, including diet soda. The wide-spread use of artificial sweeteners is partially a result of increasing problems with obesity and type 2 diabetes across the globe. CSPI encourages drinking plain, mineral or seltzer water, but diet sodas that contain artificial sweetener are still preferable to regular soda containing sugar.
Sucralose has also been associated with a higher risk for diabetes, according to The Huffington Post. Studies show that sucralose causes insulin levels to rise, which could cause a higher craving for sugar as a person's blood sugar drops. Other studies are in conflict as to whether diet soda is the cause of an increased risk of diabetes, or if it's based on a correlation wherein individuals who are part of a high-risk group are making a choice to use artificial sweeteners to reduce sugar and calories.